#ifndef _2_81_H
#define _2_81_H

#include <cmath>


/**
 *  A. (X > Y) == (-X < -Y);
 *               false, x = INT_MIN && -X = INT_MIN;
 *  B. ((X + Y) << 5) + X - Y == 31 * Y + 33 * X;
 *               true
 *  C. ~X+~Y == ~(X+Y);
 *               false x = y = 0;
 *  D. (int)(ux-uy) == -(y-x);
 *               true
 *  E. ((X >> 1) << 1) <= X;
 *               true
*/

bool test(int x, int y){
    unsigned ux = (unsigned) x;
    unsigned uy = (unsigned) y;

    return (int)(ux-uy) == -(y-x);
}


#endif // _2_81_H

